Sheet storing device, post-processing apparatus equipped with the device and image forming system equipped with the apparatus

Abstract

A sheet storing device having a conveyance device that converts the conveyance direction while holding the sheet and a storing section that has the first support member supporting the surface of the sheet substantially vertically, the second support member supporting the edge of the sheet and a pressing member pressing the sheet against the first support member, a post-processing apparatus equipped with the sheet storing device and an image forming system equipped with the aforesaid items.

1. A sheet storing device comprising:
 (i) a conveyance device which conveys a sheet in a conveyance direction and changes the conveyance direction while holding the sheet, the conveyance device comprising:
 a first belt unit including a large-diameter roller for changing the conveyance direction, a first small-diameter roller, and a first belt stretched between the large-diameter roller and the first small-diameter roller, and 
 a second belt unit including a plurality of second small-diameter rollers, and a second belt which is stretched between the plurality of second small-diameter rollers and which is in contact with the first belt at least on a portion opposed to the large-diameter roller; and 
 
 (ii) a storing section for storing the sheet conveyed by the conveyance device, the storing section comprising a first support member for supporting a surface of the sheet, a second support member for supporting an edge of the sheet, and a pressing member for pressing the sheet against the first support member, 
 wherein when conveying and storing sheets, the sheet storing device receives each sheet and overlaps a preceding sheet and a succeeding sheet of the sheets at a point where the first belt on the large-diameter roller and the second belt start to come in contact with each other, and the conveyance device holds and conveys the overlapped sheets, and then releases holding of each of the sheets so that the sheets are stored in the storing section. 
 
   
   
     2. The sheet storing device of  claim 1 , wherein the second support member has a substantial horizontal supporting surface and the second support member loads the sheet thereon by gravity force. 
   
   
     3. The sheet storing device of  claim 1 , wherein the first support member has a supporting surface substantially perpendicular to the second support member and the pressing member has a pressing surface substantially perpendicular to the second support member. 
   
   
     4. The sheet storing device of  claim 1 , wherein the conveyance device constitutes the first support member. 
   
   
     5. The sheet storing device of  claim 1 , further comprising, an urging device for urging the pressing member with a constant load, wherein the pressing member is movable along a supporting surface of the second support member. 
   
   
     6. The sheet storing device of  claim 1 , wherein the conveyance device continuously conveys the sheets with a trailing edge of the preceding sheet and a leading edge of the succeeding sheet next to the preceding sheet overlapping each other. 
   
   
     7. The sheet storing device of  claim 1 , further comprising:
 a sensor for detecting the sheet; and 
 a controller for starting the conveyance device based on a sheet leading edge detection signal of the sensor. 
 
   
   
     8. The sheet storing device of  claim 7 , wherein the controller stops the conveyance device based on a sheet trailing edge detection signal of the sensor. 
   
   
     9. The sheet storing device of  claim 1 , wherein the first and second belt units convert the conveyance direction of the sheet conveyed and introduced substantially horizontally to the first and second belt units so that the sheet is conveyed downward substantially vertically. 
   
   
     10. The sheet storing device of  claim 9 , wherein the conversion of the conveyance direction of the sheet is conducted by a conveyance along a part of a circumferential surface of the large-diameter roller of the first belt unit. 
   
   
     11. The sheet storing device of  claim 1 , wherein the conveyance device releases holding of the sheet at a point which is higher than a height of the sheet in an upright position on the second support member. 
   
   
     12. A post-processing unit comprising:
 a post-processing apparatus for folding a sheet; and 
 the sheet storing device of  claim 1  for conveying and storing the sheet folded by the post-processing apparatus. 
 
   
   
     13. An image forming system, comprising:
 an image forming apparatus for forming an image on a sheet; 
 a post-processing apparatus for folding the sheet ejected from the image forming apparatus; and 
 the sheet storing device of  claim 1  for storing the sheet folded by the post-processing apparatus.